Preventing Hospital-Acquired Venous Thromboembolism

Should low molecular weight heparin (LMWH) or unfractionated heparin (UFH) be the recommended choice for VTE prophylaxis in moderate to high-risk patients?

Because the literature demonstrates superiority of LMWH over UFH in a relatively small subset of patient populations (i.e., spinal cord injury, acute ischemic stroke, trauma, hip and knee arthroplasty, and bowel surgery for cancer patients), the Emory team decided to design a simple VTE protocol that could be applied to the majority of patients for whom efficacy is comparable. Emory found that this made it much easier to risk stratify and recommend prophylaxis options for these patients. Because only a small percentage of inpatients could be considered low risk, almost all inpatients without contraindications to pharmacologic prophylaxis would receive either UFH or LMWH.

For the several patient groups in which LMWH has demonstrated superiority, the Emory team decided it would not be difficult to customize VTE protocols. Similarly, the provider groups for patients for whom pharmacologic prophylaxis is contraindicated appreciated that the team could customize their VTE protocols to make it easy to order mechanical prophylaxis and difficult to order pharmacologic prophylaxis.

Which patients need mechanical in addition to pharmacologic prophylaxis?

The Emory team decided that mechanical prophylaxis should not be part of its recommendations for routine prophylaxis because of the very large intermediate- to high-risk group. The team did include mechanical prophylaxis as an additive option for patients with more risk factors and for patients with relative or absolute contraindications to pharmacologic prophylaxis. In the orthopedic VTE protocol, the team presented the combination of mechanical and pharmacologic prophylaxis as the recommended option.

Which patients should have 5,000 units of heparin every 12 hours versus 5,000 units of heparin every 8 hours?

The Emory team found that a portion of inappropriate prophylaxis derived from the choice of providing heparin twice a day (BID) in patients younger than 75, a group in which BID heparin is not convincingly better than placebo. So while the team wanted to reduce the frequency of BID heparin in those patients, it decided to preserve it as an option for patients older than 75. To discourage inappropriate use of BID heparin, the team indented it from the margin of the order sheet and added the qualifier "inadequate except for patients older than 75."

* Emory University Hospital is a 550-bed referral center and Emory Crawford Long Hospital is a 550-bed community teaching hospital.